The dogs were taught to lead two humans to boxes containing treats. One handler would give the dogs a treat, but the other would not.

They were then required to lead the humans to different boxes. The first would contain sausage, the second an unappealing biscuit and the third nothing at all.

They were also taught that they would be able to eat the leftover treats at the end of the session.

More often than not, they would lead the cooperative handler to the box with the sausage and the competitive handler to the empty box, indicating they knew that by deceiving the latter they would be able to get the treat later.

It’s pretty ingenious stuff.

Earlier this year, scientists in Japan pawed scorn on the idea that cats aren’t as smart as dogs.